BAGHDAD — An Iraqi health official says seven people, including three Iranian pilgrims, were killed when an explosives-laden car detonated as they were exiting a rest stop north of Baghdad.

The health official says some 30 other people were wounded in Saturday's blast in the town of Balad, some 50 miles (80 kilometers) north of Baghdad. He says the wounded were Shiite pilgrims from Iraq, Iran and Pakistan. He spoke anonymously because he wasn't authorized to talk to the media.

They were traveling from a shrine in the northern city of Samarra to another in nearby Balad.

Shiite pilgrims are often targeted by Sunni extremists who claim they aren't true Muslims. Attacks typically increase this time of year, when Shiites mourn the seventh-century killing of the Prophet Muhammad's grandson, the Imam Hussein.